Sources tend to disagree on the father of Judith of Lens (or Ponthieu). Most sources tend to give Lambert, Count of Lens as the father, while Gary Boyd Roberts in his The Royal Descents of 900 Immigrants (p. 919) gives The Carmen de Hastingae Proelio of Guy, Bishop of Amiens (1972, p. 127) as a source pointing to her mother's first husband Enguerrand II, Count of Ponthieu.